<!DOCTYPE HTML>
<html>
<head>
<title>Low Latency WebGL Canvas drawImage Test</title>
<style type="text/css">
.nomargin {
  margin: 0px auto;
}
</style>
<script>
let g_swapsBeforeAck = 15;

function waitForFinish()
{
  if (g_swapsBeforeAck == 0) {
    domAutomationController.send("SUCCESS");
  } else {
    g_swapsBeforeAck--;
    window.requestAnimationFrame(waitForFinish);
  }
}

function main()
{
  let canvas_gl = document.getElementById("c3d");
  let gl = canvas_gl.getContext("webgl", {"desynchronized": true});

  let width = canvas_gl.width;
  let height = canvas_gl.height;

  gl.enable(gl.SCISSOR_TEST);
  gl.scissor(0, 0, width, height);
  gl.clearColor(1, 0, 0, 1);
  gl.clear(gl.COLOR_BUFFER_BIT);

  gl.scissor(0, 0, width / 2, height / 2);
  gl.clearColor(0, 1, 0, 1);
  gl.clear(gl.COLOR_BUFFER_BIT);

  gl.scissor(width / 2, height / 2, width / 2, height / 2);
  gl.clearColor(0, 0, 1, 1);
  gl.clear(gl.COLOR_BUFFER_BIT);

  let canvas_2d = document.getElementById("c2d");
  let ctx_2d = canvas_2d.getContext("2d");

  ctx_2d.drawImage(canvas_gl, 0, 0);

  waitForFinish();
}
</script>
</head>
<body onload="main()">
<div id="container" style="position:absolute; top:0px; left:0px">
<canvas id="c3d" width="100" height="100" class="nomargin"></canvas>
<canvas id="c2d" width="100" height="100" class="nomargin"></canvas>
</div>
</body>
</html>
